Automatic train controlling apparatus



Aug. 21, 1934. J. P. GILLIGAN El AL 1,971,259

-. AUTOMATIC TRAIN' CONTROLLING APPARATUS Filed larch 29, 1929 2Sheets-Sheet 1 5 FIIIIIIIIIIIIIIA III.

LLLJ i r/IIIIIIII/I/IIA I N V EN 7:0R5 James P G/'/// yan. Geo/ye WEdwards.

A TTORNE Y.

Aug. 21, 1934. J p 3 ET AL 1,971,259

AUTOMATIC TRAIN CONTROLLING APPARATUS Filed March 29. 1929 2Sheets-Sheet 2 INVENTORS James P Gfl/gan.

A TTORNE Y.

Geogz Mfg Wards.

Patented Aug. 21, 1934 PATENT OFFICE AUTOMATIC TRAIN CONTROLLINGAPPARATUS James P. Gilligan and George W. Edwards, Toledo, OhioApplication March 29, 1929, Serial No. 350,915

3 Claims.

Our invention relates to automatic train controlling apparatus and hasto do with the provision of a novel control'device which cooperates withthe air brake equipment of the train and will not only be effective tostop the train under conditions of extreme danger and when the blockindicates stop, but will also be effective to stop the train when thetrain controlling appa-'- ratus isout of order to such extent that theusual track side signal fails to indicate existing danger conditions.

Our invention has to do primarily with the provision of means forpositively releasing the air in the air brake system so as to ensureapositive stopping of the train. This stopping of the train isaccomplished by means of a very simple, compact and positively actingstructure which comprises electrical control means carried by the trainand operated by striking a ramp, third rail, or other object which isnot energized, means for automatically energizing such third rail in theevent that the track is safe and the train is to proceed, and solenoidcontrol means for releasing the air brake pressure in the brake pipes ofthe train whenever the third rails are automatically de-energized or, iffor any reason,

there is a broken circuit leading to the third rails or within theelectrical system carried by the train. The third rails for controllingthe stopping of the train are, under normal safe conditions, connectedwith a current supply'and such current supply is, preferably, onlybroken in case of danger to the train resulting-for instance, from thetrain entering an already occupied block or section.

One of the objects of our invention is the provision of an air brakevalve, cylinder and piston structure for operating such valve, andsolenoid control means for normally maintaining the piston structure ininoperative position of such construction that the movement of thepisston structure for opening the air brake valve to stop the train isentirely dependent upon the de-energization of the solenoid core.

A further object of our invention is the provision of automaticallyoperating means for controlling the stopping of the train when going inone direction only and the provision of additional automatic stoppingmeans for controlling the stopping of the train when going in theopposite direction. Each particular stopping device will not affect theprogress of the train except when the train isgoing in onespecificdirection or, in other words, when the train is going forwardthe third rails on one side of the track are only effective to stop suchforward movement of the train, while the third rails on the oppositeside of the track will only be effective to stop the train when suchtrain'is going in a 4 rearward direction. Furthermore, we wish toprovide a means whereby, when the forwardly or rearwardly moving trainis positively stopped by the automatic stopping device, the trainmanmay, after descending from the locomotive and adjusting theair controlvalves, move his train 5 in the opposite direction without the trainbeing stopped again by such particular automatic stopping device.

A still further object of our invention consists in the provision of anair brake control valve for 1'9 releasing the air brake pressure in thebrake pipe system and balanced fluid and solenoid control means formoving and preventing the movement of the air control valve in onedirection only. The construction is preferably such that the solenoidwill normally prevent operation of the air control valves when energizedbut when the solenoid is de-energiaed the fluid control means will beeffective to open the valve to stop the train. However, the fluidcontrol means will not be effective 30 to close the valves which wouldpermit the train to proceed. Neither will the re-energization'of thesolenoid be effective to close the valve. Thus, the valve may be openedautomatically but must be closed manually.

A still further object of our invention is the provision of a meanswhich will prevent the building up of pressure in the brake pipe systemwhen such pressure has been been reduced to effect the apv plication ofthe'brakes of the train. This is ac: complished by a valve which isoperated simultaneously with the brake pipe pressure reducing valve topositively cut off the connection between the air pressure reservoir andthe brake pipe system. The provision or" such valve will have thefurther advantage of permitting a constant pressure to be maintained inthe main reservoir without necessitating the continual working of theair pressure pump during the time that the brakes are applied. 0

A still furtherobject of our invention has to do with the provision of apivoted trolley with contact members of unequal length carried by suchtrolley whereby, when the trolley is moved in one direction, the shorterportion of the contact memher will break'the circuit carried by thetrain and, when the trolley is moved in the opposite direction, thelongerportion of the contact member will maintain the circuit carried bythe train. Therefore, when the trolley is moved in one dinisrn is soconstructed that, if for any reason the rection by striking a thirdrail, the current for energizing the solenoid will either be supplied bysuch third rail or the solenoid will be released to eiTect the stoppingof the train. However, if the trolley is moved in the oppositedirection, the longer portion of the contact member will be effective tomaintain the. train circuit and to cause the solenoid to remainenergized. I

Another object of our invention has to do with the provision of a switchor contact mechanism in connection with the regular track switch,

which is so arranged that the contactor for permitting electric energyto be supplied to the'third rail will remain in contacting positionuntil it is positively moved by the track switch to non-contactingposition. This switch or contact mecharails are spread in such manner asto permit a train traveling on the main track to go into a sidingirrespective of manual movement of the track switch, the electric energybeing supplied to the third rail will be immediately cut off toautomatically effect stopping of the train.

Still another object of our invention has to do with the provision or"means for keeping the third rail clean at all times, regardless ofweather conditions, to ensure positive electrical contact between thethird rails and the-trolley structure for controlling the release of thesolenoid core.

A still further object of our invention has to do with the provision ofa cut-out valve equipped with electrical control means whereby any oneof the train stopping devices on a plurality of locomotives may berendered inoperative.

Many other features of our invention will be apparent as thisdescription progresses and will be brought out in the claims appendedhereto. The various objects of our invention are, preferably, obtainedby the structure illustrated in the drawings wherein similar charactersof reference designate corresponding parts and wherein:

Figure 1 is a diagrammatic side elevation of parts of a locomotive whichis equipped with our automatic train stopping mechanism, alsodiagrammatically shown.

Figure 2is an enlarged detailed View of the trolley structure shown inFigure 1, showing the unequally spaced contact member carried by thetrolley and the resilientmechanism for cleaning the third rail.

Figure 3 is a fragmentary horizontal crosssection taken on the line 3-3of Figure 2, showing the means for insulating the trolley member againstelectrical contact with the locomotive.

Figure 4 is a diagrammatic plan and elevational view showing a switchstructure for connecting a track switch with a third rail and astructure, controlled by a semaphore, for energizing or de-energizinganother third rail.

Figure 5 is a diagrammatic perspective View showing thesystem of wiringused on a locomotive.

Figure 6 is a top plan view of the device shown in Figure 5.

Figure 7 is a detailed side elevation partly in section, of the valvestructures and operating mechanism therefor of my apparatus, showing thevalves in the positions which they normally occupy.

Figure 8 is a detailed side elevation, partly in section, similar toFigure 7, showing the valves in the positions they occupy when thebrakes of the train are applied. 7

In the drawings, our automatic train stopping device is shown ascomprising a valve 1 which controls the release of the air brakepressure in the brake system for stopping the train. This valve 1 isobviously carried by the locomotive but, in Figure 1, we havediagrammatically shown this valve with the air brake and electricalbrake controlling mechanism of the locomotive.

As best shown in Figure 1, the air control valve is connected to astandard air brake pipe 2 of the locomotive. The valve is preferablyprovided with an operating cam element 3, the cam element being movablein one direction only by means of a suitable piston rod 4 that forms apart of the piston 5 which, in turn, reciprccates within a suitable aircylinder 6. The piston rod 4 is not connected with the valve cam element3 but ismerely designed to contact with one face of such cam element tomove the cam element and the valve to open position to release the airbrake pressure from the train brake pipe.

The piston rod 4 is pivotally connected to one end of a lever 8 which is:fulcrumed on thelocomotive frame as at 9. The lower end of this lever 8is preferably pivotally connected to a rod 10 whereby any oscillation ofthe lever 8 will be effective to move the rod 10 horizontally within itsbearing supports or, in other words, the lever 3 may be oscillated aboutthe fulcrum 9 while the rods l and 16 are horizontally reciprocable.Therod 10 is connected at one end to the solenoid core 11. This solenoidcore 11 forms a part of a suitable solenoid 12. H

As best shown in Figure 1, the cylinder 6 is directly connected with theair brake pressure pipe leading from the main airpressure reservoir 14by means or the pipe 13 and one face of the piston 5 is subjected to airpressure from the main reservoir 14 in such manner that the normal airpressure in the main reservoir will constantly be effective upon thepiston 5,'tending to move the piston in one direction only. However, inthe normal operation of our device, the electric current passing throughthe solenoid 12 will be effective to produce enough pull on the solenoidcore 11 so that the tendency of the air pressure in the main reservoirto move the piston 5 will be overcome as long as the solenoid 12 isenergized. It will be understood that air pressure taken from any sourcemay be used instead of air pressure from the main reservoir with equaleffectiveness.

At. the instant that the solenoid 12 is deenergized for any causewhatever, and the pulling force on the solenoid core 11 released, themain reservoir air pressure on the piston 5 will be efiective to movesuch piston and its piston rod 4, whereby the piston rod l contactingwith the surface of the valve cam 3 will move the valve lever to openthe valve 1. Opening of the valve 1 will release the air pressure in theair rake pipe 2 to the atmosphere thereby causing application of thetrain brakes to stop the train.

Our device is provded with a valve 1 operated by the rod 4% when thevalve 1 is operated. The valve 1 is designed to be normally opened sothat the air pressure contained in the main reservoir limay pass to theengineers brake valve but the operating arm of the valve 1 is soconnected to the operating arm :of the valve 1 that the valve 1? isclosed simultaneously with the opening of the, valve 1 to releasethebrake pipe pressure. This closing of the valve l will effectivelyprevent the main reservoir air from passing to the engineers automaticbrake valve and from there into the brake pipes thereby possibly causingthe brakes to be inadvertently released when they" should remainapplied. This arrangement has the further advantage 'ofx'positivelyclosing off. any escape of air pressure from the main reservoir 1.4which will eliminate the necessity of. having the brake pipe. pressurepump constantly working in an effort to keep up pressure in the brakepipe pressure reservoir while the brakes are applied.

An independent brake valve 15 is also shown in Figure 1. This brakevalve is manually operated by means of .a lever lfiand may be usedindependently of the automatic brake control.

In Figures 1 and 2 we have shown a trolley. 17 that'is pivotedpreferably to the forward'part of the locomotive frame as at 18. Thistrolley is normally held in vertical position by means of the coilsprings 19 which bear against opposite sides thereof as shown best inFigure 2. Such pivoted trolley is adapted, when in vertical position, toact as the contact armofa switch and is adapted to connect a contact 20with a'contact 21. As will be seen by referring to the drawings, thecontacts 20 and 21 are separated and the trolley 17 is provided with amember 22 that is adapted to make connection between these contacts.

The contacts 20 and 21 are preferably mounted on the locomotive frameand the contact 20 is constantly supplied with current from a battery23, also carried by the locomotive, by meansof a wire 24 connected to awire 30 which leads to the battery. The contact 21 is, in turn,connected to the solenoid 12 by means of'a wire 26 and a wire 25'. Suchsolenoid is grounded, for instance, to the locomotive frame, and whenthe trolley is in' normal'or vertical position, current will iiow fromthe battery 23 to and through the so-lenoidby way of the wires 30 and24, contact 20, contact member 22 on the trolley'17, contact 21 and thewires 26 and 25, together with the ground wire leading from thesolenoid. It will be apparent, therefore; that a break in the circuitfrom the battery 23 to and through the solenoid 12 will cause thesolenoid to be de-energized'. Such deenergization of the solenoid 12will permit the air pressure from the air brake line to be released tothe atmosphere, thereby applying the brakes.

It will be noted that the contact member 22 has arms of unequal lengthon opposite sides of the trolley 17 and that, when the trolley is innormal vertical position, a greater portion of the contact arm 22overlaps the contact 21 than overlaps the contact 20. The longer arm ofthe contact me n ber 22 extends rearwardly of the trolley 17 withrespect to the normal direction of travel of the train, as best shown inFigures 1 and 2.

In the event that the trolley strikes a: third rail when the train ismoving forwardly, such trolley will be moved in the opposite directionas shown in Figure. 1, thereby breaking the connection between thecontacts 20 and 21 and causing a break in the circuit from thebattery'23 to and through the solenoid 12 thatwas hereinbeforedescribed. Such break in the circuit will cause the solenoid to becomecle-energized and permit move ment of the piston 5 to open the valve 1and set the brakes. However, in the event that the train is movingbackwardly and the trolley strikes a third rail, thetrolley will bemoved in a direction opposite that in which it would be moved if thetrain were following its forwardly or normal direction of travel. Inthisinstance, the longer arm of the contact member 22 will stillmaintain a connection between the contacts 20 and'2l thereby causing thecircuit from the battery2S to-and through the solenoid to. remainunbroken'whereby thev solenoid will remainenergized and prevent movementof the piston 5. tov open the valve 1; and set. the brakes.

.The trolley li'is adaptedtocontact with suita ble third rails 27 asindicated" in. Figure land, as shown in this. figure, the third rails.27 have a relatively steep incline at; their rearward end and are thengradually inclinedtowardsi their forward end. In the operation of. ourdevice, the third railsr27 are energized.andide-energized in accordancewith the conditionof the trackas regards trains thereon or the operationof a block signal system and such energization and de energization. iscontrolled by a track relay and the. movement of. semaphore signalswhichresult from electrical impulses through such track relay. Theenergi- Zation and de-energization of the third rails.2.7. will behereinafter described in detail.

In order to control the stopping of. a trainwhen the train is travelingin a reverse direction from its normal direction of travel, we haveprovided a trolley structure on the opposite side of the locomotive asshown in Figures 5: and 6. This trolley structure isthe exact duplicateof. the trolley structure just described, with the exception that theentire structure is reversed, and is connected in serieswiththepreviously described. trolley structure. For example, the trolleystructure above referred to comprises atrolley 17 conetacts 2G and 21and a contact member 22 carried bythe trolley. However, the relativep.osi-' tionsoi the contact 20 and 21 are reversed from that positionwhich the contacts 21'). and 21 occupy with relation toeach other andthecontact member 22 is reversed with relation to the trolley 1.7. I Asshown in Figures 5 and 6, the trolley structures on each side of theengine are connected in series with the battery 23 and the solenoid 12and, at the same time, the battery 23 may have direct connection withthe solenoid if desired. In the normal operation of the. device,electrical current flows from the battery 23 through the wires 30 and 24to the contact member 20, thence through. the contact member 22, contact21, wire 28, contact 21, contact member 22., contact 20 and wires 31 and32to the solenoid 12. However, electric current may flow from thebattery 23 and wires 30, 31 and 32. direct to the solenoid 12 withoutpassing through the contacts 20, 21, 20 and 21'. This will take placewhen the contacts of the switch structure 63' (see Figure 5) are.connected.

Since the trolley structures are on opposite sides of the locomotive,connected in series with the same battery and solenoid and the positionof the trolley structure parts are reversed with relation to each other,the trolley structure on one side of the locomotive will be effective todisconnect the contacts 20 and 21 to break the circuit from the batteryto the solenoid on striking a third rail when the train is movingbackwardly' but will maintain a connection between the contacts 20 and21 on striking the same or a similarthird rail when the train is movingforwardly. The reverse will be true of the trolley structure on theopposite side of the locomotive, it being effective to break the circuiton striking a third rail when the train is moving forwardly butineffective on striking a third rail when the train is movingbackwardly.

With the use of the two trolley structures hereinbefore described, itwill be necessary that third rails. be placedon both. sides of. the.track and nected to th that these third rails be reversed. That is, thehighest points of the third rails on one side of the track would be atthe rearward end thereof while the highest pointsof the third rail on.the opposite side of the track would be at the forward end thereof withrespect to the normal direction of travel of the train. Further, thethird rails on the respective sides of the track would necessarily beinclined in opposite directions for reasons hereinafter apparent.

In the operation of this part of the apparatus, it will be seen that thesolenoid is normally maintained energized throughthe circuit justdescribed and that a break in the connection between either the contacts20 and 21 or the contacts 20' and 21' will cause a break in such circuitand the consequent de-energization of the solenoid 12. With the thirdrails that are placed on opposite sides of the track having theirhighest points at opposing ends and being inclined in opposite directionwith respect to the normal direction of travel of the train, connectionbetween the contacts 20 and 21 will be broken when the trolley 17strikes a third rail as the train is moving forwardly and connectionbetween the contacts 2c and 21 will be broken when the trolley 17strikes a third rail as the trainis moving rearwardly. It will thus beapparent that while one trolley structure will be effective to .causede-energization or" the solenoid when the train is moving forwardly, thetrolley structure on the. opposite side of the locomotive will beefiective to cause de-energization of the solenoid 12 when the train ismoving rearwardly.

As previously stated, the third rails 2'7 are energized or de--energizedin accordance with the condition of the track asregards trains thereonor the operation of a block signal system and such energization anddeenerg'-ization is controlled by a track. relay and the movement ofsemaphore signals which result from electrical impulses through suchtrack relay. It will be understood that, in the usual block signalsystem, the signals are usually operated from a main station at somepoint along the track and relays,

one at or near each individual signal.

In Figure 4 of the drawings, one semaphore signal and its means forcontrolling the energizaticn-or de-energization of a third rail 2'7 isdiagrammatically shown. As shown in this figure, a semaphore signal33 isprovided with a switch structureS l, the contactor 35 of which isconnected to the signal arms 36 and adapted to be operated by movementthereof. A relay 37 that may or may not form a part of the usualtrackside signal operating relay (not shown) is located adjacent thesemaphore signal 33. It is well understood in the art, that the positionof the semaphore signal arms 36 is controlled by electrical energyeither shorted out, transmitted the relay to a third rail 27. Anotherwire 44 leads from the relay 3? to one contact 45015 the semaphoresignal operated switch 34 and the other contact of the switch isconnected to the contactor arm 3'7 of the relay by a wire 47. Thebattery, third rail and switch are connected and electrical energy sthrough the relay 3'? that mayor may not form a part of the tracksidesignal operating relay (not shown) which con-' 1 trols the position ofthe semaphoresignal arms 36.

relay 37 and a wire as leading from.

toenergize the third rail 27 when the contactor 37' of the relay 37 isinthe position shown.

'CIn'the operation of this part of the apparatus, namely, the control ofthe energization or deenergization of the third rail 27, completecircuit to the third .rail 27 is made when the semaphore 'signalarms 36are in safety or proceed position and the contactor arm 37 is incontacting position with relation to the main body of the relay 37. Withthecontactor 35 and the contactor arm 37' in the above positions,current will flow from the battery 42,.through the relay 37, wire 47,contact 46, contactor 35, contact 45, wire 4.4, relay 3'? and wire 43 tothe thirdrail 2'7. The connection between the contactor 35 and thesemaphore signal arms 36 is such that the same circuit will be alsomaintained when the semaphore signal arms 36 are in such position as toindicate to proceed with caution. However, when the semaphore signalarms 36 are in danger indicating position, the contactor 35 will nolonger connect the contacts 45 and 48V and the above circuit will bebroken, resulting in the third rail being (ls-energized.

As the circuit on the engine is broken by the trolley 17 striking thehighest point on the third rail 27, the contactor 22 will be moved awayfrom the contact 20 and the trolley 1'1 will pick up the current fromthe third rail 2'7.v This current will flow through the solenoid 12,which is grounded to the engine frame by way of the contact 21 and wire26' to hold the core 11 in the normal closed position. However, when thetrolley 17 strikes a de-energized third rail, due to the semaphoreswitch being in danger position, the contactor 22 wvill be moved out ofcontact with the contact 25 and the circuit on the locomotive will bepositively broken. Therefore, the solenoid 12 will be-- matic brakevalve 63.

Providing the trolleyl'? strikes a charged third rail while the train istraveling forwardly, current from the energized third rail will flow tothe solenoid 12 as long as the trolley 17 is in contact with the thirdrail but, as the train passes forwardly, the trolley will be graduallyreturned to normal position in passing over the sloping portion of thethird rail so that contact will be made between the contacts 20 and 21before the trolley 17 leaves such third rail and still maintain thesolenoid 12 energized. The same will be true of the trolley 17 andthe'contacts'20. and 21' in the event that the trolley strikes anenergized third rail when the trainis backing up.

The trolley mechanism is preferably insulated against electrical contactwith the locomotive frame in the manner best shown in Figure 3. Anypreferred form of insulating material may be used to insulate thetrolley pivot 18 and the spring carrier 47 but it is preferred that theybe insulated as shown at 48, 49 and 50.

The forward end of the locomotive frame is provided with a casting 51 inwhich reciprocates a spring pressed rod 52. The lower end of this springpressed rod is provided with a brush 54, made of some suitablenon-conducting material, designed to resiliently contact with the thirdrail 27 just in front of the pivoted trolley 17. The object of thisbrush structure is to provide a means for keeping the third rail" 27'clean at all times so as to ensure positive electrical'contact betweensuch third rail and the trolley.

A brush 55, made of some current conducting.

material, is supported by the casing 51 by means of a spring pressed rod56. The rod 56 is insulated as at57 and the brush 55 is connected to thecontact 21 by means-of the wire 58. The brush structure 55 is placeddirectly behind the trolley 17' and makes a connection between the thirdrail 27 and the contact 21 in the event the trolley 17 is broken orfails to function properly.

In instances where it is necessary to employ a plurality of locomotivesequipped with our automatic train controlled apparatus, such devices onany one of the locomotives may be rendered inoperative by moving the arm59 to move the contactor 66 into contact with the contacts 61 and 62. Byreference to Figure 1, it will be apparent that the contacts 61 and 62are connected to the solenoid 12 and the battery 23 by the wires 25 and25 respectively, and that, when the contacts 61 and 62 are connected,electric energy is carried directly to the solenoid 12 from the battery23 through the wire 30, switch structure and wire 25, irrespective ofany movement on the part of the trolley 1'7. In this way the solenoidcore is held in closed position and the automatic train stopping deviceis prevented from operating. The same effect may be had by using theswitch structure 63 (see Figure 6) to complete the circuit from thebattery 23, through wires 30, 31 and 32, to and through the solenoid 12.

As hereinbeiore stated, the third rail 27 whose energization iscontrolled by the semaphore operated switch 34 is connected to the relay37 by the wires 44 and 47. The relay 3'7 is, in turn, connected to thebattery 42. As a locomotive passes over an energized third rail, theelectric current is picked up by the trolley 1'7 and is transmitted tothe solenoid 12 by the means hereinbefore described.

With reference to Figure 4, we have shown therein a track side circuitassociated with the ramp 65 that is designed to be interrupted when therail points of the switch are aligned with the side track or spur. Thus,when the switch is open, the ramp 65 will be deenergized, therebyprotecting the trafiic approaching such switch from entering the samewhen open.

The track side circuit preferably consists of a battery 72, lead 71,contact 69, contact bar 68 associated with the switch lever 67, contact69' and lead '70 to the ramp 65. The negative pole of the battery '72 isconnected to one of the rails of the main line, preferably the one thatis negatively charged by wire '71.

In operation, assuming that the rail points of the switch are alignedwith the main line, the circuit to such ramp will be completed throughwire '71, contact 69, contact bar 68, which has been moved into contactwith each of the contacts 69 and 69 by the closing of the switch, wire70 to the ramp 65. When the trolley of the locomotive circuit interceptsthe charged ramp 65, current will flow through either of the brush 55 tothe wire 26 and 25 and thence to the solenoid 12, or will pass throughthe trolley arm to the contact 22, through contact 21, wires 26' and 25,solenoid 12, through the ground to'one of the track rails, the circuitbeing completed by the wire '71 extending from the negative pole of thebattery 72 to the track rail.

With such an arrangement, it will be impossible for a locomotive toenter an open. Switch,

inasmuch as spreading of the rail pointslby the lever 67 automaticallyinterrupts the circuit and deenergizesthe ramp 65 which resultantlydeenergizes the solenoid 12 of an approaching locomotive and effects thestopping of the train in a manner set out hereinbeiore. V

We have provided a novel means for prevent,- ing the building up ofpressure in the brake pipe system when such pressure has once beenreducedto effect an application of the brakes. This is accomplished byplacing the valve l between the independent brake valve 15 and'the usualengineers emergency brake valve 63. As hereinbefore described, thisvalve 1 is operated by and simultaneously with the valve 1 which opensthe" brakeipipe 2 to the atmosphere to release the pressure therein. Thevalve 1 is so constructed. as to be positively closed when the valve 1,is open and to be open when the valvel is closed. It will be apparentthat by closing the valve 1 all'com munication between the mainreservoir 14 and the brake pipe 2 is cut off. This will have the addedadvantage of permitting a constant pressure to be maintained in the mainreservoir 14 without the necessity of continual working of the usual airpressure pump during the time that the brakes are applied.

It will be apparent that we provide an automatic train stopping devicewhich, when a signal is in danger indicating position or the rail pointsof a track switch are in dangerous position, will be eiiected todeenergize the corresponding third rail. This third rail causes thetrolley 1'? to move rearwardly, thus breaking the circuit between thebattery 23 and the solenoid 12 which will permit release of the airbrake pressure to stop the train. Furthermore, since the automatic trainstopping device is caused to operate as a result of a deenergized thirdrail, in the event that the current wires leading to such third rail aregrounded or broken the train will be automatically stopped irrespectiveof the position of the semaphore or track-side switch.

It will further be apparent that our novel train stopping apparatus isso constructed that operative relation between the third rail and thetrolley structure will be assured under all conditions of speed,weather, wear, oscillation or shock. The trolley will always strike thethird rails irrespective of whether or not such rails are energized I25and, if for any reason a trolley should stick in its oscillated positionafter passing an energized third rail, the train will be automaticallystopped until the trolley is moved to its normal position in which itconnects the contacts '20 and 21. will further be apparent that thebrake pipe pressure releasing valve 1 and the cam element 3 are moved inone direction only by the piston rod 4, and that, in order to close thevalve 1 after it is once open, it will be necessaryto manually move thevalve to its closed position before the train may proceed.

Having thus described our invention, what we claim is:

1. Train control apparatus comprising a brake pipe system, an airreservoir for supplying air under pressure to said brake pipe system,valve means for controlling the supply of air under pressure deliveredfrom said air reservoir to said brake pipe system, a valve in said brakepipe system for venting the air under pressure in said brake pipesystem, mechanical means for connecting said valves together to producesimultaneous operation thereof, means cooperating with said mechanicalmeans for effecting the' opening of one of said valves and the closingof the other of said valves, said means being moved in one direction bya fluid motor and in the opposing direction manually.

2. -Train control apparatus comprising a brake pipe system, an airreservoir for supplying air under pressure to said brake pipe system, avalve for controlling the supply of air under pressure delivered fromsaid air reservoir to said brake pipe system, a valve in said brake pipesystem said means being-inefiective to return said valves to theiroriginal positions.

3. Train control apparatus comprising a brake pipe system, an airreservoir for supplying air under pressure to said brake pipe system, a,valve for controlling the supply of air under pressure delivered fromsaid air reservoir to said brake pipe system, a valve in said brake pipesystem for venting the air under pressure in said brake pipe system,mechanical means for connecting said valves together to producesimultaneous operation thereof, means cooperating With said mechanicalmeans for effecting the opening of one of said valves and the closing ofthe other of said valves, said means being moved in one direction by afluid motor and in the opposing direction manually, and solenoid controlmeans for normally preventing operation of said fluid motor.

- JAMES P. GILLIGAN.

GEORGE W. EDWARDS.

